The RSF Kobol is a French monophonic synthesizer released in 1978, described by some as "the French Minimoog". It could process external sounds to through the envelope and filter section. It was created by Ruben and Serge Fernandez. Fewer than 200 were made as they were not mass-produced. The Kobol is a very versatile instrument, offering many sought-after features of other analogue synthesizers of its time.